The purpose of this project is to investigate the neural regulation of the onset of puberty. It is hypothesized that during the onset of puberty the slow wave field potentials of certain cell populations in the brain, i.e., the arcuate nucleus (ARC), pre-optic area (POA) and amygdala(AMY), responsible for the release of gonadotropin releasing hormone (GN-RH) are altered not only with respect to their individual activity, but also with respect to how their activities relate to one another. To test this hypothesis, slow wave field potentials (signals) of the three areas of the brain, ARC, POA, and AMY, are simultaneously recorded during the onset of puberty in normal female rats and during the estrous cycle in the adult stage. Primary analog data are digitized and analyzed by cross-correlation technique which indicates the degree of correlation of the signals appearing in different areas, the direction and temporal sequence of signal flow, feedbacks, and hidden pulses and periodicities in noise. By use of this technique it is possible to assess how singles in the AMY, ARC, and POA interact at puberty and to relate them to changes seen in these areas in the adult cycling rat. We are also determining if the changes seen in the rat going through puberty can be altered in time by electrical stimulation of the AMY. In addition, the frequencies of signals recorded from each area are being determined.